13. Menene matakan kariya don auna CODCR?
Ma'aunin CODCr yana amfani da potassium dichromate azaman oxidant, sulfate na azurfa azaman mai haɓakawa a ƙarƙashin yanayin acidic, tafasa da sakewa na awanni 2, sannan kuma ya canza shi zuwa amfani da iskar oxygen (GB11914-89) ta hanyar auna yawan amfani da potassium dichromate.Ana amfani da sinadarai irin su potassium dichromate, mercury sulfate da sulfuric acid mai mai da hankali wajen auna CODCr, wanda zai iya zama mai guba sosai ko kuma ya lalace, kuma yana buƙatar dumama da reflux, don haka aikin dole ne a yi shi a cikin hurumin hayaƙi kuma dole ne a yi shi sosai.Ruwan sharar gida Dole ne a sake yin fa'ida kuma a zubar dashi daban.
Domin inganta cikakken hadawan abu da iskar shaka na rage abubuwa a cikin ruwa, azurfa sulfate bukatar da za a kara a matsayin mai kara kuzari.Domin ya sa sulfate na azurfa ya rarraba daidai, ya kamata a narkar da sulfate na azurfa a cikin sulfuric acid mai mahimmanci.Bayan an narkar da shi gaba daya (kimanin kwanaki 2), acidification zai fara.na sulfuric acid a cikin kwalban Erlenmeyer.Hanyar gwaji ta ƙasa ta nuna cewa 0.4gAg2SO4 / 30mLH2SO4 ya kamata a ƙara don kowane ma'auni na CODCR (samfurin ruwa na 20mL), amma bayanan da suka dace sun nuna cewa don samfuran ruwa na gabaɗaya, ƙara 0.3gAg2SO4 / 30mLH2SO4 ya isa gaba ɗaya, kuma babu buƙatar buƙata. amfani da karin Azurfa sulfate.Don samfuran ruwan najasa da ake auna akai-akai, idan akwai isasshen sarrafa bayanai, ana iya rage adadin sulfate na azurfa daidai.
CODCr alama ce ta abubuwan da ke cikin kwayoyin halitta a cikin najasa, don haka dole ne a cire amfani da iskar oxygen na ions chloride da abubuwan rage inorganic yayin aunawa.Don tsangwama daga abubuwan rage inorganic kamar Fe2+ da S2-, ƙimar CODCR da aka auna za'a iya gyara gwargwadon buƙatun iskar oxygen da aka auna dangane da ƙaddararsa.Tsangwama na ions chloride Cl-1 ana cire gabaɗaya ta hanyar mercury sulfate.Lokacin da ƙarin adadin shine 0.4gHgSO4 a cikin samfurin ruwa na 20mL, za'a iya cire tsangwama na 2000mg/L ions chloride.Don samfuran ruwan najasa akai-akai tare da ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun abubuwa, idan abun ciki na chloride ƙarami ne ko kuma ana amfani da samfurin ruwa tare da ma'aunin dilution mafi girma don aunawa, ana iya rage adadin sulfate na mercury daidai yadda ya kamata.
14. Mene ne catalytic inji na azurfa sulfate?
Hanya na jan hankali na sulfate na azurfa shine cewa mahadi masu ɗauke da ƙungiyoyin hydroxyl a cikin kwayoyin halitta an fara oxidized ta potassium dichromate zuwa carboxylic acid a cikin matsakaiciyar acidic.Fatty acid da aka samar daga kwayoyin halitta na hydroxyl suna amsawa tare da sulfate na azurfa don samar da fatty acid azurfa.Saboda aikin atom na azurfa, ƙungiyar carboxyl na iya samar da carbon dioxide da ruwa cikin sauƙi, kuma a lokaci guda suna samar da sabon azurfa mai fatty acid, amma carbon atom ɗinsa bai kai na farko ba.Wannan sake zagayowar yana maimaitawa, sannu a hankali yana oxidizing duk kwayoyin halitta zuwa carbon dioxide da ruwa.
15.Mene ne matakan kariya don auna BOD5?
Ma'aunin BOD5 yawanci yana amfani da daidaitaccen dilution da hanyar inoculation (GB 7488-87).Aikin shine sanya samfurin ruwan da aka cire, cire abubuwa masu guba, da diluted (tare da adadin inoculum mai dacewa wanda ya ƙunshi ƙananan ƙwayoyin cuta wanda aka kara idan ya cancanta).A cikin kwalban al'ada, sanya a cikin duhu a 20 ° C na kwanaki 5.Ta hanyar auna abubuwan da aka narkar da iskar oxygen a cikin samfuran ruwa kafin da kuma bayan al'ada, ana iya ƙididdige yawan amfani da iskar oxygen a cikin kwanaki 5, sa'an nan kuma za'a iya samun BOD5 bisa tushen dilution.
Ƙaddamar da BOD5 shine haɗin gwiwa sakamakon ilimin halitta da sinadarai kuma dole ne a aiwatar da shi daidai da ƙayyadaddun aiki.Canza kowane yanayi zai shafi daidaito da kwatankwacin sakamakon aunawa.Sharuɗɗan da ke shafar ƙayyadaddun BOD5 sun haɗa da ƙimar pH, zafin jiki, nau'in microbial da yawa, abun ciki na gishiri inorganic, narkar da iskar oxygen da dilution factor, da dai sauransu.
Dole ne a cika samfuran ruwa don gwajin BOD5 kuma a rufe su a cikin kwalabe na samfur, kuma a adana su a cikin firiji a 2 zuwa 5 ° C har sai an bincika.Gabaɗaya, yakamata a yi gwajin a cikin sa'o'i 6 bayan samfurin.A kowane hali, lokacin ajiya na samfuran ruwa bai kamata ya wuce sa'o'i 24 ba.
Lokacin auna BOD5 na ruwan sha na masana'antu, tun da ruwan sharar masana'antu yawanci yana ƙunshe da ƙarancin narkar da iskar oxygen kuma yana ƙunshe da mafi yawan kwayoyin halitta masu lalacewa, don kula da yanayin aerobic a cikin kwalbar al'ada, samfurin ruwa dole ne a diluted (ko inoculated da diluted).Wannan aiki Wannan shine babban fasalin daidaitaccen hanyar dilution.Don tabbatar da amincin sakamakon da aka auna, yawan iskar oxygen na samfurin ruwa mai narkewa bayan al'ada na kwanaki 5 dole ne ya fi 2 MG / L, kuma ragowar narkar da iskar oxygen dole ne ya fi 1 mg / L.
Manufar ƙara maganin inoculum shine don tabbatar da cewa wasu ƙananan ƙwayoyin cuta suna lalata kwayoyin halitta a cikin ruwa.Adadin maganin inoculum ya fi dacewa kamar yadda yawan iskar oxygen a cikin kwanaki 5 bai wuce 0.1mg/L ba.Lokacin amfani da distilled ruwa shirya da wani karfe distiller a matsayin dilution ruwa, ya kamata a kula don duba karfe ion abun ciki a cikinsa don kauce wa hana microbial haifuwa da kuma metabolism.Domin tabbatar da cewa narkar da iskar oxygen a cikin ruwa mai narkewa yana kusa da jikewa, ana iya gabatar da iska mai tsabta ko oxygen mai tsabta idan ya cancanta, sa'an nan kuma sanya shi a cikin incubator na 20oC na wani lokaci don daidaita shi tare da matsa lamba na ɓangaren oxygen a ciki. iska.
An ƙaddara ƙimar dilution bisa ka'idar cewa yawan iskar oxygen ya fi 2 MG / L kuma sauran narkar da iskar oxygen ya fi 1 mg / L bayan kwanakin 5 na al'ada.Idan sinadarin dilution ya yi girma ko kuma karami, gwajin zai gaza.Kuma saboda sake zagayowar binciken BOD5 yana da tsawo, da zarar irin wannan yanayin ya faru, ba za a iya sake gwada shi kamar yadda yake ba.Lokacin da aka fara auna BOD5 na wani ruwan datti na masana'antu, da farko za ku iya auna CODCR ɗinsa, sannan ku koma ga bayanan kulawa da ake da su na ruwan datti mai kama da ingancin ruwa don fara tantance ƙimar BOD5/CODCr na samfurin ruwan da za a auna, sannan ku lissafta. m kewayon BOD5 dangane da wannan.da kuma ƙayyade abubuwan dilution.
Don samfuran ruwa da ke ɗauke da abubuwan da ke hanawa ko kashe ayyukan rayuwa na ƙwayoyin cuta na aerobic, sakamakon aunawa kai tsaye BOD5 ta amfani da hanyoyin gama gari zai ɓace daga ainihin ƙimar.Dole ne a yi maganin da ya dace kafin aunawa.Wadannan abubuwa da abubuwan suna da tasiri akan ƙaddarar BOD5.Ciki har da karafa masu nauyi da sauran abubuwa masu guba na inorganic ko kwayoyin halitta, ragowar chlorine da sauran abubuwan da ke haifar da iskar oxygen, darajar pH da ta yi yawa ko kadan, da sauransu.
16. Me ya sa ya zama dole don yin allura yayin auna BOD5 na ruwan sharar masana'antu?Yadda ake yin allurar?
Ƙaddamar da BOD5 shine tsarin amfani da iskar oxygen biochemical.Kwayoyin halitta a cikin samfuran ruwa suna amfani da kwayoyin halitta a cikin ruwa azaman abubuwan gina jiki don girma da haifuwa.A lokaci guda, suna lalata kwayoyin halitta kuma suna cinye narkar da iskar oxygen a cikin ruwa.Sabili da haka, samfurin ruwa dole ne ya ƙunshi adadin ƙananan ƙwayoyin cuta waɗanda zasu iya lalata kwayoyin halitta a cikinsa.iyawar microorganisms.
Ruwan sharar masana'antu gabaɗaya ya ƙunshi nau'ikan abubuwa masu guba daban-daban, waɗanda zasu iya hana ayyukan ƙwayoyin cuta.Saboda haka, adadin ƙananan ƙwayoyin cuta a cikin ruwan sharar gida na masana'antu kadan ne ko ma babu su.Idan aka yi amfani da na yau da kullun na auna ma'auni mai wadatar ƙazanta na ƙazanta na birni, ƙila ba za a iya gano ainihin abubuwan da ke cikin ruwan datti ba, ko aƙalla su yi ƙasa.Misali, ga samfuran ruwan da aka yi amfani da su tare da zafin jiki mai zafi da haifuwa kuma wanda pH ya yi yawa ko ƙasa kaɗan, ban da ɗaukar matakan riga-kafi kamar sanyaya, rage ƙwayoyin cuta, ko daidaita ƙimar pH, don tabbatar da tabbatar da ingancin magani. daidaiton ma'aunin BOD5, dole ne kuma a ɗauki ingantattun matakai.Alurar riga kafi.
Lokacin auna BOD5 na ruwan datti na masana'antu, idan abubuwan da ke cikin abubuwa masu guba sun yi yawa, ana amfani da sinadarai a wasu lokuta don cire shi;idan ruwan datti ya kasance acidic ko alkaline, dole ne a cire shi da farko;kuma yawanci samfurin ruwa dole ne a diluted kafin a iya amfani da misali.Ƙaddamarwa ta hanyar dilution.Ƙara adadin da ya dace na maganin inoculum mai ɗauke da ƙananan ƙwayoyin cuta na gida zuwa samfurin ruwa (kamar cakudawar tankin da aka yi amfani da shi don magance irin wannan ruwan sha na masana'antu) shine sanya samfurin ruwa ya ƙunshi adadin ƙananan ƙwayoyin cuta waɗanda ke da ikon lalata kwayoyin halitta. al'amari.A karkashin yanayin cewa sauran sharuɗɗan auna BOD5 sun cika, ana amfani da waɗannan ƙananan ƙwayoyin cuta don lalata kwayoyin halitta a cikin ruwan datti na masana'antu, kuma ana auna yawan iskar oxygen na samfurin ruwa na tsawon kwanaki 5 na noma, kuma za'a iya samun darajar BOD5 na ruwan datti na masana'antu. .
Haɗaɗɗen ruwa na tankin iska ko ƙazamin tanki mai najasa na biyu na masana'antar kula da najasa shine kyakkyawan tushen ƙwayoyin cuta don tantance BOD5 na ruwan dattin da ke shiga masana'antar sarrafa najasa.Inoculation kai tsaye tare da najasar gida, saboda akwai kadan ko babu narkar da iskar oxygen, yana da haɗari ga fitowar ƙwayoyin cuta na anaerobic, kuma yana buƙatar dogon lokaci na noma da haɓakawa.Sabili da haka, wannan ingantaccen maganin inoculum ya dace ne kawai ga wasu ruwan sharar masana'antu tare da takamaiman buƙatu.
17. Menene hattara don shirya ruwan dilution yayin auna BOD5?
Ingancin ruwan dilution yana da matukar mahimmanci ga daidaiton sakamakon ma'aunin BOD5.Don haka, ana buƙatar iskar oxygen na ruwan dilution wanda ba shi da komai na kwanaki 5 dole ne ya zama ƙasa da 0.2mg/L, kuma yana da kyau a sarrafa shi ƙasa da 0.1mg/L.Amfanin iskar oxygen na ruwan dilution da aka shafe tsawon kwanaki 5 yakamata ya kasance tsakanin 0.3 ~ 1.0mg/L.
Makullin tabbatar da ingancin ruwan dilution shine don sarrafa mafi ƙarancin abun ciki na kwayoyin halitta da mafi ƙarancin abun ciki na abubuwan da ke hana haɓakar ƙwayoyin cuta.Sabili da haka, yana da kyau a yi amfani da ruwa mai tsabta a matsayin ruwan dilution.Ba a so a yi amfani da ruwa mai tsafta da aka yi daga resin musayar ion a matsayin ruwan dilution, domin ruwan da aka cire sau da yawa yana Kunshi kwayoyin halitta da aka ware daga resin.Idan ruwan famfo da aka yi amfani da shi don shirya ruwa mai narkewa ya ƙunshi wasu ƙwayoyin halitta masu canzawa, don hana su zama a cikin ruwa mai narkewa, sai a yi pretreatment don cire kwayoyin halitta kafin a distillation.A cikin distilled ruwa samar daga karfe distillers, ya kamata a mai da hankali ga duba karfe ion abun ciki a cikin shi don kauce wa hana haifuwa da kuma metabolism na microorganisms da kuma rinjayar da daidaito na BOD5 auna sakamakon.
Idan ruwan dilution da aka yi amfani da shi bai dace da buƙatun amfani ba saboda ya ƙunshi kwayoyin halitta, ana iya kawar da tasirin ta hanyar ƙara adadin inoculum na tanki mai dacewa da adana shi a cikin dakin zafin jiki ko 20oC na wani ɗan lokaci.Adadin inoculation yana dogara ne akan ka'idar cewa yawan iskar oxygen a cikin kwanaki 5 shine game da 0.1mg / L.Don hana haifuwa algae, dole ne a gudanar da ajiya a cikin dakin duhu.Idan akwai laka a cikin ruwan da aka narke bayan ajiya, za a iya amfani da maɗaukaki kawai kuma za'a iya cire shi ta hanyar tacewa.
Domin tabbatar da cewa narkar da iskar oxygen da ke cikin ruwan dilution yana kusa da jikewa, idan ya cancanta, ana iya amfani da injin famfo ko mai fitar da ruwa don shakar da iska mai tsafta, kuma ana iya amfani da na'urar kwampreshin iska don allurar da iska mai tsafta, da kuma iskar oxygen. Ana iya amfani da kwalban don gabatar da iskar oxygen mai tsabta, sannan kuma ruwan oxygenated Ruwan da aka shafe ana sanya shi a cikin 20oC incubator na wani ɗan lokaci don ba da damar narkar da iskar oxygen ta kai ga daidaito.Ruwan dilution da aka sanya a ƙananan zafin jiki a cikin hunturu na iya ƙunsar narkar da iskar oxygen da yawa, kuma akasin haka shine gaskiya a lokutan zafi mai zafi a lokacin rani.Sabili da haka, lokacin da akwai bambanci mai mahimmanci tsakanin zafin jiki da 20oC, dole ne a sanya shi a cikin incubator na wani lokaci don daidaita shi da yanayin al'ada.oxygen partial matsa lamba balance.
18. Yadda za a ƙayyade ma'aunin dilution lokacin aunawa BOD5?
Idan ma'aunin dilution ya yi girma ko ƙanƙanta, yawan iskar oxygen a cikin kwanaki 5 na iya zama kaɗan ko kuma ya yi yawa, ya ƙetare iyakar amfani da iskar oxygen na al'ada kuma yana haifar da gwajin ya kasa.Tun da sake zagayowar ma'aunin BOD5 yana da tsayi sosai, da zarar irin wannan yanayin ya faru, ba za a iya sake gwada shi kamar yadda yake ba.Sabili da haka, dole ne a ba da hankali sosai ga ƙaddarar ƙwayar dilution.
Kodayake abun da ke tattare da ruwan sharar masana'antu yana da rikitarwa, rabon darajar BOD5 zuwa ƙimar CODCR yawanci tsakanin 0.2 da 0.8.Adadin ruwan datti daga yin takarda, bugu da rini, da masana'antun sinadarai sun yi ƙasa, yayin da rabon ruwan datti daga masana'antar abinci ya fi girma.Lokacin auna BOD5 na wasu ruwan datti mai ɗauke da kwayoyin halitta, kamar ruwan sharar hatsi na distiller, rabon zai ragu sosai saboda abubuwan da ke tattare da su suna haɗe a kasan kwalabe na al'ada kuma ba za su iya shiga cikin halayen biochemical ba.
Ƙayyadaddun ma'auni na dilution ya dogara ne akan yanayi guda biyu cewa lokacin aunawa BOD5, yawan iskar oxygen a cikin kwanaki 5 ya kamata ya fi 2mg / L kuma sauran narkar da iskar oxygen ya kamata ya fi 1mg / L.DO a cikin kwalban al'ada a ranar bayan dilution shine 7 zuwa 8.5 MG / L.Yin la'akari da cewa yawan iskar oxygen a cikin kwanaki 5 shine 4 MG / L, mahimmancin dilution shine samfurin ƙimar CODCr da ƙididdiga uku na 0.05, 0.1125, da 0.175 bi da bi.Misali, lokacin amfani da kwalban al'ada na 250mL don auna BOD5 na samfurin ruwa tare da CODCr na 200mg/L, abubuwan dilution guda uku sune: ①200 × 0.005 = sau 10, ②200 × 0.1125 = 22.5 sau, da ③205 × 0.17 sau 35.Idan ana amfani da hanyar dilution kai tsaye, adadin samfuran ruwa da aka ɗauka sune: ①250÷10=25mL, ②250÷22.5≈11mL, ③250÷35≈7mL.
Idan ka ɗauki samfurori da al'ada su kamar wannan, za a sami sakamakon narkar da iskar oxygen na 1 zuwa 2 wanda ya dace da ka'idodin biyu na sama.Idan akwai ma'auni guda biyu na dilution waɗanda suka dace da ƙa'idodin da ke sama, yakamata a ɗauki matsakaiciyar ƙimar su yayin ƙididdige sakamakon.Idan sauran narkar da iskar oxygen ta kasa da 1 MG / L ko ma sifili, ya kamata a ƙara adadin dilution.Idan narkar da iskar oxygen da aka narkar da lokacin al'ada bai wuce 2mg / L ba, yuwuwar ɗayan shine cewa sinadarin dilution ya yi girma;sauran yuwuwar ita ce nau'ikan ƙwayoyin cuta ba su dace ba, suna da ƙarancin aiki, ko haɓakar abubuwa masu guba ya yi yawa.A wannan lokacin, ana iya samun matsaloli tare da manyan abubuwan dilution.Gilashin al'ada yana cinye ƙarin narkar da iskar oxygen.
Idan dilution ruwa ne inoculation dilution ruwa, tun da oxygen amfani da blank ruwa samfurin ne 0.3 ~ 1.0mg / L, dilution coefficients ne 0.05, 0.125 da kuma 0.2 bi da bi.
Idan an san ƙayyadaddun ƙimar CODCR ko kusan kewayon samfurin ruwa, zai iya zama da sauƙi don nazarin ƙimar BOD5 bisa ga ma'aunin dilution na sama.Lokacin da ba a san kewayon CODCr na samfurin ruwa ba, don rage lokacin bincike, ana iya ƙididdige shi yayin tsarin ma'aunin CODCR.Hanyar da ta dace ita ce: da farko shirya daidaitaccen bayani mai dauke da 0.4251g potassium hydrogen phthalate a kowace lita (ƙimar CODCr na wannan maganin shine 500mg/L), sannan a tsarma shi daidai da ƙimar CODCr na 400mg/L, 300mg/L, kuma 200mg./L, 100mg/L dilute bayani.Pipette 20.0 ml na daidaitaccen bayani tare da ƙimar CODCR na 100 mg/L zuwa 500 mg/L, ƙara reagents bisa ga hanyar da aka saba, kuma auna ƙimar CODCR.Bayan dumama, tafasa da refluxing na minti 30, kwantar da hankali zuwa yanayin zafin jiki sannan a rufe da adana don shirya daidaitaccen jerin launi.A cikin aiwatar da auna ma'aunin CODCR na samfurin ruwa bisa ga hanyar da aka saba, lokacin da tafasasshen tafasa ya ci gaba na tsawon mintuna 30, kwatanta shi da daidaitaccen daidaitaccen ƙimar ƙimar ƙimar CODCR don kimanta ƙimar CODCR na samfurin ruwa, kuma ƙayyade dilution factor lokacin gwada BOD5 dangane da wannan..Don bugu da rini, yin takarda, sinadarai da sauran ruwan sharar masana'antu mai ɗauke da wahalar-narke kwayoyin halitta, idan ya cancanta, yi kimantawar launi bayan tafasa da sakewa na mintuna 60.
Lokacin aikawa: Satumba-21-2023
